Salt
Possibly because of its antimicrobial properties or because of how often it's used in religious rituals, salt has long been used as a Vampire-Be-Gone.
- In Romanian folklore, it was believed that women who ate a lot of salt during pregnancy would have a normal baby. However, if you craved a low-sodium diet, you were destined to give birth to a bouncing baby bloodsucker. Just imagine the joys of nursing that would bring!
- Ever make your parents so mad that they damn you to a postmortem vampire existence? Yep, we've all been there. Well, Greek folklore talks about using saltwater to reverse this very specific situation of a parent-initiated vampire curse.
- Used as a tracking device, salt would be dumped on the bedroom floor of a vampire victim. The idea was that the vampire would step in the salt and the salt would stick to his bare, vampy feet, which would then allow the Buffys, Van Helsings, and Winchester Brothers of the world to follow the saline path back to the vampire's grave.
Seeds
It would appear that vampires suffered from extreme forms of OCD. According to ancient European peasant folklore, you could keep a vampire from rising and disturbing the peace if you filled his coffin with seeds. Upon waking from his dirt nap, the vampire would be compelled to count and eat all the seeds, and this would keep him occupied until sunrise. You could use carrot or mustard seed, but poppyseeds were favored because of their narcotic effect. After all, a drugged vampire is not a biting vampire.
Garlic
It would appear that during those annoying flare-ups of the Black Plague in the 1300s, people used garlic to mask the delightful scents of death and dying. Before it was known that the Black Plague was, in fact, a plague with explainable roots in rats, people assumed that sudden high body counts were the work of vampires and thus developed the association between garlic and vampires. (A lot of medical mysteries were blamed on poor, misunderstood vampires in the olden days.)
There's also a Christian myth that spins a tale of Satan stomping around the Garden of Eden. Supposedly, garlic sprouted from his left footprint after he, Adam, and Eve were tossed out on their asses. Not totally sure what that has to do with vampires, since it seems more like an explanation why Satan could have benefitted from Tinactin, but stranger associations have been made.
Lard
Because it falls five days before Christmas on the Eastern Orthodox calender, Romanians slaughtered pigs on St. Ignatius Day. (I dearly want to call it "St. Pignatius Day," but I'm afraid of the heavenly ramifications.) They then took the rendered fat and gave "suspicious corpses" a thorough rub-down with it.
The reasoning behind this porcine massage is not clear, but it's just another excuse to keep Fatted Calf bacon on hand.
Vampire Blood
People in Poland believed that if you ate bread made with the blood of a freshly-staked vampire, you'd be protected against vampire attacks. Romanians took it a step further and consumed the entire body. They'd chop up and burn the body of a suspected vampire then mix the ashes with water. This potent potable was drunk by the vampire's surviving family to prevent them from vamping out themselves.
This "vampire vaccine" was used to inoculate relatives of a suspected vampire as recently as 2004.